Worlds Without End: Exoplanets, Habitability, and the Future of Humanity

In this stimulating survey, Impey (Einstein’s Monsters), an astronomy professor at the University of Arizona, takes readers on a tour of notable planets beyond our solar system, or exoplanets. He covers the scientific advances and discoveries made since the 1995 identification of the first exoplanet—a body half the mass of Jupiter that circles its star in a “blistering four-day” year—launched a proliferation of research that has led contemporary astronomers to posit that “about 60 percent of sunlike stars have a habitable, earthlike planet.” Explaining the sophisticated techniques scientists developed for studying exoplanets, Impey describes how astronomers infer details about atmosphere and chemical composition from the changes undergone by starlight as it passes through an exoplanet’s atmosphere on its way to Earth, revealing planets with 5,400 mph winds and temperatures hot enough to vaporize metal. The author also discusses efforts to find life elsewhere in the cosmos, including the European Space Agency’s plans to search one of Jupiter’s moons and a Russian philanthropist’s quest to send nanobots to planets orbiting the star nearest to our sun. Impey strikes the right balance between accessibility and scientific rigor, and the glimpses into the extreme conditions on distant planets will whet readers’ curiosity. Armchair astronomers will be entranced. (Apr.)